Air conditioning apparatus



Feb. 17, 1942. L. D. HOULIS AIR CONDITIONING APPARATUS Filed April 15, 1939 4 Sheets-Sheet l INVENTOR. ,Lou/s D. /oul/s ATTO NEY.

Feb. 17,- 1942. D. 'HC:)UL|S 2,273,357

" AIR CONDITIONING APPARATUS Filed April 15, 1959 4 Sheets-Sha 2' l aufs 0 Hou/fs Feb. 17, 1942. uus I 2,273,357

AIR CONDITIONING APPARATUS Y Filed April 15, 1939 4 Sheets-Sheet 3 Ira-HI Lou/ls .0. Hog/As Feb. 17, 1942; L. D. u 2,273,357

AIR CONDITIONING APPARATUS Filed April 15, 1959 I 4 Sheets-Sheet 4 I INVENI'OR.

pose is eliminated.

Patented Feb. 17, 1942 UNITED STATES PATENT OFFICE AIR CONDITIONING APPARATUS Louis D. Houlis, Cincinnati, Ohio Application April 15, 1939, Serial No. 267,988 4 Claims. (oi. 235-44) stat which is disposed in the path of the oilculating air and which controls the temperature thereof; the humidity of the air being controlled by a wet bulb thermostat which is also located within the unit in the path of the circulating air.

Another object of the invention is to provide an improved air conditioning unit wherein the admittance of steam alone is depended upon to control the humidity of the air, whereby the necessity of utilizing heated water for this pur- A particular object of the invention is to provide an improved apparatus, of the character described, having a humidity controlof the wet bulb type for regulating and controlling the humidity of the circulating air, said control being so arranged that the wet bulb action is obtained without the. necessity of immersing the same in wateror enclosing the same in a wet cover or sock, whereby the entire area of the control element is'expose'd to the circulating air and a more sensitive and positive control obtained.

Another object of the invention is to provide an improved air conditioning unit wherein steam is admixed with the circulating air to-control humidity of the air being regulated and controlled by a humidostat which maybe located either in advance of theheating and humidifying means or behind said means near the outlet side of the casing, the arrangement making for a simple and compact structure which efficiently.

and accurately controls the temperatureand humidity of the circulating air.

A construction designed to carry out the in-' vention will be hereinafter described, together with other features of the invention.

The invention will be more readily understood from a reading of the following specification said unit being provided with a dry bulb thermoand by reference to the accompanying drawings, in which an example of the invention is shown; and wherein:

Figure 1 is a perspective view of a baker's proof box, having an air conditioning apparatus, constructed in accordance with the invention, mounted thereon for conditioning the air which is circulated through said box,

Figure 2 is a partial plan view of the air conditioning unit, constructed in accordance with the invention,

Figure 3 is a partial side elevation of said unit,

. having a portion of its wall broken away to more clearly show the interior thereof,

the humidity thereof. together with means for utilizing the steam condensate or water for maintaining the bulb or element of the ,humidostat in a moistened condition, whereby the use of auxiliary water in the system is entirelyeliminated.

A further object of the invention is' to provide an improved air conditioning unit having Figure 4 is a-transverse, vertical, sectional view, taken on the line 4-4 of Figure 2,-

Figure 5 is a plan view of a modified form of the invention and having portions of its top broken away to clearly illustrate the interior,

Figure 6 is aside elevation of the unit shown in' Figure 5, with the portions of the side wall broken away,

. Figure '7 is a transverse, vertical, sectional view, taken through one of the steam jets,

Figure 8 is a plan view of still another form of the invention, and

Figure 9 is aside elevation of this form of the invention.

In the drawings, the numeral [0 designates a housing which is substantially rectangular in cross-section. The housing; may be formed in any suitable manner and is provided with insulated walls which have vertical air inlet ducts H secured thereto. The upper ends of the inlet ducts H are connected to a longitudinally extending manifold I! which overlies the top of the housing. .The manifold is connected with an air conditioning unit A. which will be hereinafter described and the conditioned air is circulated through the manifold and into the vertical ducts -ll. From the ducts, the conditioned air passes through openings 13 and into the interior of the housing. The air escapes from the interior of the housing through openings l4 provided in vertical outlet ducts |5 which are disposed on the wall opposite the ducts The upper ends .of the outlet ducts |5 are connected with a longitudinally extending manifold l6, which overlies the top of the housing and said manifold is connected to the air conditioning unit A. Manifestly, conditioned air is constantly has risen and is otherwise ready for the baking operation. While the dough is within the box l0, it is necessary that the temperature and humidity of the air which is circulatingvthrough said box be maintained at the predetermined and desired point. The box is, of course, provided with suitable hinged doors l0, whereby access to the interior thereof may be readily had.

The invention primariLv resides in the conditioning unit A which, as shown, is mounted on the top of the box or housing l0. It is noted that the box or housing l0 forms no part of the present invention and has been shown merely to'illustrate one use of the conditioning unit A. The unit A could be employed for maintaining the proper temperature and humidity 4 conditions within the fermentation room of a bakery or it could be employed for properly regulating and maintaining the condition of air which is circulated through any closed chamber or enclosure.

The conditioning unit A includes an elongate casing which is substantially rectangular in cross-section, as is clearly shown in Figure 2. An inlet opening 2| is formed in one end wall of the casing 20 and this opening is surrounded by an outwardly directed flange '22, to which the manifold l6 may be connected, whereby air is introduced into the interior of the casing. A blower housing 23 is mounted within the casing and is secured to the end wall opposite that in which the inlet opening 2| is provided. The housing 23 has a suitable fan. or blower 24 mounted therein and adjacent the fan the housing is formed with an opening 25. The shaft of the fan projects through the end wall of the casing 20 and is coupled to a suitable electric motor or other drive means 21, which motor is supported on a bracket secured to the exterior of the casing. When the motor 21 is operated to rotate the blower or fan 24, air is drawn longitudinallv through the casing, said air being pulled from the manifold I6 so as to flow toward the opening 25 in the blower housing 23.

The air which is drawn'into the blower housing by the fan 24 is forced outwardly from said housing through an outlet opening 23, which is provided in the side wall of the casing 20. The

- thermostat, of the pipes 33 ofthe radiator opening 29 is surrounded by a flange 30 to which the manifold I2 is connected. With this arrangement, it will be manifest that the fan 24 serves to draw the air from the manifold l3, through the casing 20 and then outwardly through the manifold; l2. From the manifold H, the air passes downwardly through the vertlcal ducts ll, then transversely of the box or radiator is'located nearer to the inlet opening 2| and includes the usual headers 32, which have the transversely extending steam pipes 33 disposed therebetween. The headers are secured to the side walls of the casing by suitable angle bars 34. Steam is supplied to one of the headers 32 by an inlet pipe 35 which extends throughthe side wall ofthe casing 20, as is clearly shown in Figures 2 and 3. A thermostatically operated valve 38 is connected in the line 35 and this valve, as will be hereinafter explained, is adapted to control the admittance of steam to the radiator 3|.

A hand operated control valve 31 is also connected in the inlet pipe 35 and beyond said valve the pipe is coupled to a T 38. The T has connection with an inlet line 39 which leads from a suitable source of steam supply. Manifestly, when the hand valve 31 is opened, the control of steam to the radiator 3| is accomplished by means of the thermostatically operated valve 36.

The valve 36 is controlled by a thermostat 40 which is connected tosaid valve by the usual flexible cable 4|. The thermostat 40 is mounted in the top of the casing 20 immediately adjacent the inlet opening 2|, whereby the bulb or element 42 of said thermostat depends downwardly into the interior of the casing and directly in the path of the air entering the interior thereof. The bulb or element has been shown in the form of a coil, but it is pointed out that any suitable dry bulb type. andsuch as may be purchased on the open market, may be employed.

The thermostat 40 may be adjusted to maintain the temperature of the circulating air at a desired point. If the temperature falls below such a point, the thermostat acts to open the valve 36' and admit more steam to the steam 3|. Such action will cause a heating of the air circulating through the casing, with the result that the temperature of said air will be raised. 01' the air reaches a predetermined point, the dry bulb thermostat 40 acts to close the valve 36 and shut down the steam supply to the radiator, whereby continued heating of the air is halted. In this manner, the thermostat provides a positive means of regulating and controlling the temperature of the circulating air. Since the element 42 of the thermostat is disposed directly in the path of the circulating air and has its 44 which extends laterally and transversely of the casing and projects through the side walls thereof. The line 44 has a thermostatically operated valve 45 connected therein and also has When the temperature.

a hand valve 46 beyond the thermostatic valve.

' Beyond the valve to, the line It is extended and is coupled to the T 38 which has the steam line 39 connected therein. In this manner, the perforated spray pipe 43 is supplied with steam from the line 39, said steam passing throughv the pipe "44 and past the manually' operated valve 46 and stat 40. Theelement 4a ofthe thermostat is in the form of a coil and extends substantially throughout the vertical length oi the casing 20 and this coil is filled with a suitable gas or other fluid, which is responsive to, or affected by, temperature changes. Since the thermostat is located adjacent the thermostat 40, the element 49 of said thermostat is disposed directly in the path of the air entering the casing. A

It is well-known that a thermostat of the wet bulb type. must have its element maintained in a moist or wet condition in order to properly operate. For maintaining the element 49 in a moistened condition, a wick ill is disposed within the coil of said element and has its upper end suitably fastened within the upper end thereof.-

The lower end the wick extend "from the lower end of the element and is locatedjinthe bottom of the casing 20. Some of the. steam which is ejected into the interior of the casing from the steam spray pipe 43 will condense and precipitate to the bottom of the casing. This condensatewill, of course, be water and will accumulate within the lower end of the casing, as shown in Figures Sand 4. A predetermined level of this water is maintained in the bottom of the casing since the water outlet pipe Si is spaced unit 52 is mounted. The unit 52 extends transversely of the casing and is secured to the side walls thereof by suitable angle bars SI. The unit includes a plurality of offset baffles 54 which extend vertically throughout the height of the casing. The baflies in one-half of the unit are oiiset in a direction opposite to the baflles in the other side of the unit, as is clearly shown in Figure 2. This arrangement provides for an unrestricted continuous passage 55 at the center of the batlie unit. The air which is passing through the casing must pass through the batfle unit and, as it strikes the offset baiiies and passes therebetween, it is caused to take a circuitous path, whereby the excessive moisture or water in the air is knocked out. The air which flows through the central passage 45 is not subiected to. any of the baffles but may pass directly to the blower or fan 24. For controlling the .flow of air through the passage 55,- a vertically extending, pivotally mounted damper 55a may be mounted centrally of the baiiie unit and may be readily adjusted to control the flow of air through said passage.

a predetermined distance from the bottom of said casing. Therefore, the wick 50 will depend downwardly into the water which is stored in the lower end of the casing 20 and capillary attraction will draw the water upwardly into the wick 50. The wick is thus maintained in a wet condition and this saturated wick will serve to maintain the element 49 of the thermostat 41 in a moistened condition, whereby its operation is assured.

With the above arrangement, it is not necessary to immerse the thermostat element 49 in water and neither is it necessary to enclose the same in a wet cover or sock. Thus, 'the entire In the operation of the device. the thermostat 40 is adjusted to a predetermined point.

whereby the temperature of the air which is being circulated will be maintained at that point. Similarly, the wet bulb thermostat 41 is adjusted so that the humidity of the air circulating through the casing will also be maintainedat a predetermined point. When the electric motor 21 is operated to operate the fan or blower 24.

air is drawn into the casing 20 through the in let opening 2|. This incoming air strikes the element 42 of the thermostat 40 and causes said thermostat to act in the event that the temperature of said air is not at the proper point.

If the temperature of the, air is below that at which it is desired to maintain the same. the thermostat 40 operates the valve 36 to admit more steam to the radiator 3|. Thus, the air flowing throu h the casin will pass through the steam pipes 33 of the radiator and its temperature will be raised. a

The incoming air will also strike-the element 49 of the wet bulb thermostat 41' and in the event that the humidity of this air is below that at which the' thermostat is adjusted. then said thermostat will open the valve to admit steam,

' to the spray ipe 43, whereby steam will be adouter surface of the element 49 is exposed at all times to the circulating air and this brings about a much more sensitive and accurate control. It will be evident that if the circulating air falls below a predetermined humidity, the thermostat 41 will operate the valve 45 to admit steam to the pipe 44 and the spray 43. whereby steam will be introduced into the air. The addition of this steam will immediately raise the humidity of said air and when said humidity reaches a predetermined point, as controlled by the adjustment of the thermostat 41, the valve 45 is closed to shut off the admission of steam. In this manner. a

most sensitive and accurate control of the humidity of the air circulating through the casing is obtained. a

Beyond the steam spray pipe .43 and within ,the interior the casing 20, a suitable baiiie mltted into the interior of the easing into con.- tact with the air flowing therethrough. Steam will be admitted from the spray pipe 43 in accordance with the lack of proper humidity. Thus. it will be seen that the two controls 40 and 41 accurately control the temperature and humidity condition of the air. f

After contactin the elements 42 and 49 of the thermostat and the wet bulb thermostat respectively, the air passes through the steam pipes 33 of the radiator 3|, after which said air flows past the steam spray pipe 48. If steam is being admitted, this st am will be admixed with the air to raise the humidity thereof. After passing the steam pipe 43 the air flows through the baiiie unit 52. As has been explained, the ollfset baiiles cause the air to take a circuitous path therethrough, whereby excessive moisture or water is knocked out of the air. This moisture and water will be caught by the baflles and will flow downwardly along said bodies by gravity and to the lower end of the casing 20, After passing fan or blower housing 23 and is then forced outwardly through the outlet 29 for re-circulation.

The device comprises a compact and unitary structure which'will accurately control the temperature and humidity condition of the air circulated therethrough. The thermostat 41 is of the wet bulb type and the arrangement provides for maintaining the element 49 ina moistened or wet condition, without covering the exterior sur- -face of said element, whereby increased sensitivity of control may be obtained. If desired, the upper end or top of the casing 20-may be provided with an access opening 56 which is normally closed by a suitable cover (not shown). Also the radiator 3| may be provided with the usual steam trap 51 which is connected by means of,

an elbow 58 to the lower end or bottom of the casing, whereby the condensate is conducted to said lower end. The device comprises a minimum number of parts and any desired spray head or means can be employed in place of the particular steam spray pipe 43 which is illustrated. The blower or fan 24 may be any of the well knovn types now on the open market and may be driven by any suitable means other than the motor 21.

' It is not essential that the wet bulb thermostat 41 be located adjacent the inlet opening 2| of the casing and. in Figures to 7, said thermostat is shown as located between the baflle unit 52 and the blower housing 23. In this form of the invention, the thermostat operates in the same manner to control the humidity of the air circulating through the interior of the casing. As is clearly shown in Figure 5, said thermostat is alined with the central passage 55 which is formed in the baflie unit, whereby a direct and unrestricted how of air may strike the thermostat element 49.

In this form of the invention, the wick 50 is eliminated and in place of said wick a vertically extending tube 60 is disposed within the coil of the element 49.' The tube is bent upon itself at its lower end so as to extend parallel to the bottom of the casing 20 and this lateral portion 6| projects into the battle unit 52. Upon entering the baffle, the tube is bent upwardlyto provide a vertical portion 82 which has its upper end communicating with a funnel 63. The funnel is secured to oneside of the baflle unit 52.

The funnel 63 is adapted to catch the steam condensate which flows downwardly through the pipe 62 and then upwardly through the tube 60. This condensate, which is water, overflows the upper end of the pipe and trickles downwardly within the element 49, whereby said element is maintained in a moistened or wet condition. It is noted that, if desired, this method of maintaining the element 49 in a moistened condition could be utilized when the thermostat is located in the position shown in Figures 2 to 4. a

As has been pointed out, the spray pipe 43, illustrated in the first form, may be eliminated and other means for admitting steam provided. In Figures 5 and 6, another form of steam inlet is shown. In this instance, an angular steam inlet pipe 44' is connected with the T 38 which has the steam supply line 39 connected therewith. The 'pipe 44 has the manually operated valve 46 and the thermostatically operated valve connected therein. The inner end of the pipe 44' is connected with a laterally extending pipe 64 whichis located .near the bottom of the easing 20. The pipe 64-has a plurality of steam jets 65 connected therein. Each jet includes a body 96, as shown in Figure 7, which is provided with an outlet nozzle 61 in its upper end. The steam which is admitted to the pipe 64 is ejected upwardly from the nozzle 61, as is clearly shown by the arrows in Figure 6. The body 66 is formed with diametrically opposed lugs 68 in which are supported a pair of eduction tubes 69. The lower end of each tube 69 extends into the water in the bottom of the casing 20, while the upper end of said tube is bent inwardly so as to extend contiguous to the nozzle 61.

5 When the valve 45 is operated to admit steam to the pipe 54, the steam is ejected upwardly from the nozzle 61. The ejection or emission of the steam from the nozzle 61 creates a suction in the tubes 69, whereby water is drawn upwardly through the tubes 69 and admixed with the steam. This water is sprayed upwardly in the path of the airwhich is moving through the casing 20 and a portion of this water is caught by the funnel 63. This water, as has been explained, flows downwardly from the funnel 63 through the pipe 62 and then upwardly in the tube 60. The provision of the eduction tubes 69 assures that suflicient water will fall downwardly through the funnel to maintain the element 49 in a moistened or wet condition. Of course, the water of the air when the same falls below a predetermined point.

In Figures 8 and 9,'still another form of the invention is shown. In this form, a wet bulb thermostat 41, similar in construction to the wet bulb thermostat 41, is located between the baiiie unit 52 and the blower housing 23. The thermostat 41' is formed with a solid rod or element 49' instead of with a coiled element, as is the thermostat 41. As is clearly shown in Figure 8, the thermostat is located in alinement with the passage in the bafiie unit 52.

The interior construction of this formis substantially the same as that shown in Figures 2 to 4, with the exception that a water spray pipe 10 is disposed between the steam pipe 43 and the baffle unit 52. As is clearly shown in Figure 8, the pipe 10 extends transversely of the casing and is supported in suitable brackets 1! which are located at substantially mid-height of said casing. The pipe is provided with a plurality of spray heads 12 which are directed so as to eject waterinto the path of the circulating air. The

pipe 10 is connected with a water inlet line 13 which may lead from a suitable source of water supply. The water may be ejected continuously from the spray heads 12 and it will be obvious that as the air passes through said spray, said air is washed. The excessive water which may be introduced into the air by the spray is knocked out by the baflles 54. passes through the unrestricted passage 55, which is controlled by the damper 55a, is laden with water and this stream of air will contact the rod or element 49' of the thermostat. This moisture-laden stream of air is sufficient to maintain the element 49' in a moistened or wet condition, whereby the operation of the thermostat 41' is assured. With this arrangement, the moisture-laden air is utilized to maintain the thermostat element 49' moistened and the necessity of immersing said element in water or enclosing the same with a wet cover or sock, is eliminated. The operation or this form of the However, the air whichinvention is substantially the same as the other forms, hereinbefore described.

It is pointed out that in all forms the dry bulb thermostat 40 maintains and regulates the closing said element are eliminated, and this provides for a very sensitive and accurate control. The steam alone is utilized toadd humidity to the circulating air and this eliminates the 1 necessity of providing heatedwater to control humidity. In the form shown in Figures 8 and 9,

' size, shape and materials, as well as in the details of the illustrated construction, may be made,

within the scope of the appended claims, without departing from the spirit of the invention.

What I claim and desire to secure by Letters Patent is:

1. An air conditioning apparatus including, an elongate casing having an inlet at one end and outlet at its opposite end, meansfor circulating air longitudinally through the casing, a heater extending transversely of the casing for heating the air passing therethrough, a thermostat having a dry bulb disposed between the heater and inlet directly in the path of the incoming air for controlling the operation of the heater to maintain the circulating air at a desired temperature; a steam spray means within the casing beyond the heater for introducing steam into the air circulating through the casing to control the humidity thereof, a thermostathaving a wet bulb element mounted in the casing beyond the spray means for controlling the admission of steam in accordance with-the humidityof the circulating air, and means for directing an uninterrupted stream of moistureladen air onto the element of the wet bulb thermostat to maintain the same in a moistened condition without covering the exterior surface thereof.

2. An air conditioning apparatus including, an

elongate casing having an inlet at one end and an outlet at its opposite end, means for circulating air longitudinally through the casing, a

heater extending transversely of the casing for heating the air passing therethrough, a thermostat having a dry bulb disposed between the heater and inlet directly in the path of the inheater to maintain the circulating air at a desired temperature, a steam spray means within the casing beyond the heater for-introducin steam into the air circulating through the easing to control the humidity thereof, a thermostat having a wet bulb element mounted in the casing beyond thev spray means for controlling the admission of steam in accordance with the humidity of the circulating air, and a battle unit between the steam spray means and the wet bulb thermostat for separating excessive water from the circulating air, said baiiie having an unrestricted passage alined with the element of the wet bulb thermostat, whereby a constant stream of moisture-laden air is directed onto said element to maintain the same in a moistened condition;

3. An air conditioning apparatus including, an elongate casing having an inletat one end and an outlet at its opposite end, means for circulating air longitudinally through the casing, a heater extending transversely of the. casing for heating the air passing therethrough, a thermostat having a dry bulb disposed between the heater and inlet directly in the path of the incoming air for controlling the operation of the heater to maintain the circulating air at a desired temperature, a steam spray means within the casing beyond the heater for'introducing steam into the air circulating through the easing to control the humidity thereof, a thermostat having a wet bulb element mounted in the casing beyond the spray means for controlling the admission of steam in accordance with the humidity of the circulating air, a water spray between the steam spray and wet bulb thermostat for introducing water into the casing, and a baiiie unit between the water spray and the wet bulb thermostat for separating excessive water from the circulating air, said baflle having,

an unrestricted passage alined with the element of the wet bulb thermostat, whereby a constant stream of moisture-laden air is directed onto saidelement to maintain the same in a mois- 4 tened condition.

' i. An air conditioning apparatus including, an

elongate casing having an inlet at one end and an outlet at its opposite end, means for circu-' .heater to maintain the circulating air at a' dey sired temperature, a steam spray means within the wet bulb thermostat, whereby a constant.

- coming air for controlling the operation of the I stream of moisture-laden air is directed onto saidv through.

'the casing beyond the heater for introducing casing beyond the spray means for controlling the admission of steam in accordance with the humidity of the circulating air, a baifle. unit between the steam-spray means and the wet bulb thermostat for separating excessive water from the circulating air, said baflle having an unrestricted passage alined with the element of element to maintain the same in a moistened condition, and an adjustable damper in said passage for. controlling theair flowing there- LOUIS, n; Hooms. I 

